Wireless radio telephones enable the telephone handset to be carried about the house so that telephone calls can be answered or initiated without the need to return to the point at which the base unit is connected to a public carrier network, such as the telephone company facilities. Thus, a homeowner can relax by the backyard pool and still use the telephone.
While many forms of entry intercom systems have been described, none are known to provide on an economical basis the ease of installation, reliability and over-all convenience of the cordless telephone. Such prior intercom systems are typically subject to difficulty in installation, limitations on portability, requirements for significant additional equipment, limited compatibility with existing telephone equipment, or other limitations and shortcomings.
It is therefore an object of this invention to provide integrated cordless telephone and entry intercom systems utilizing intercom, base and handset units designed to operate efficiently together with the portability, ease of operation and reliability of a cordless telephone system.
A further object is to provide such systems wherein the handset unit closely resembles existing cordless telephone handsets, the base unit relatively closely resembles existing cordless telephone base units with changes to permit operation as a radio repeater for intercom communication, and a relatively inexpensive intercom unit is arranged to be mounted near a residence entry without requiring signal or electrical wiring connections.
Further objects are to provide such systems utilizing base units providing a radio repeater function on an economical basis mainly employing components and capabilities already common in typical radio telephone base units, such systems which provide ease of installation and operation, and new and improved intercom/telephone systems which avoid one or more disadvantages of previously available systems.